ASTM_C_1368_-_18.pdf

Designation:C136818Standard Test Method forDetermination of Slow Crack Growth Parameters ofAdvanced Ceramics by Constant Stress Rate StrengthTesting at Ambient Temperature1This standard is issued under the fixed designation C1368;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of slow crackgrowth(SCG)parameters of advanced ceramics by usingconstant stress rate rectangular beam flexural testing,ring-on-ring biaxial disk flexural testing,or direct tensile strength,inwhich strength is determined as a function of applied stress ratein a given environment at ambient temperature.The strengthdegradation exhibited with decreasing applied stress rate in aspecified environment is the basis of this test method whichenables the evaluation of slow crack growth parameters of amaterial.NOTE1This test method is frequently referred to as“dynamicfatigue”testing(1-3)2in which the term“fatigue”is used interchangeablywith the term“slow crack growth.”To avoid possible confusion with the“fatigue”phenomenon of a material which occurs exclusively under cyclicloading,as defined in Terminology E1823,this test method uses the term“constant stress rate testing”rather than“dynamic fatigue”testing.NOTE2In glass and ceramics technology,static tests of considerableduration are called“static fatigue”tests,a type of test designated as stressrupture(See Terminology E1823).1.2 Values expressed in this test method are in accordancewith the International System of Units(SI)and IEEE/ASTM SI10.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:3C1145 Terminology of Advanced CeramicsC1161 Test Method for Flexural Strength of AdvancedCeramics at Ambient TemperatureC1239 Practice for Reporting Uniaxial Strength Data andEstimating Weibull Distribution Parameters for AdvancedCeramicsC1273 Test Method for Tensile Strength of MonolithicAdvanced Ceramics at Ambient TemperaturesC1322 Practice for Fractography and Characterization ofFracture Origins in Advanced CeramicsC1499 Test Method for Monotonic Equibiaxial FlexuralStrength of Advanced Ceramics at Ambient TemperatureE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE337 Test Method for Measuring Humidity with a Psy-chrometer(the Measurement of Wet-and Dry-Bulb Tem-peratures)E1823 Terminology Relating to Fatigue and Fracture TestingIEEE/ASTM SI 10 American National Standard for Use ofthe International System of Units(SI):The Modern MetricSystem3.Terminology3.1 Definitions:3.1.1 The terms described in Terminologies C1145,E6,andE1823 are applicable to this test method.Specific termsrelevant to this test method are as follows:3.1.2 advanced ceramic,na highly engineered,high-performance,predominately nonmetallic,inorganic,ceramicmaterial having specific functional attributes.(C1145)3.1.3 constant stress rate,na constant rate of maximumstress applied to a specified beam by using either a constantloading or constant displacement rate of a testing machine.1This test method is under the jurisdiction of ASTM Committee C28 onAdvanced Ceramics and is the direct responsibility of Subcommittee C28.01 onMechanical Properties and Performance.Current edition approved Jan.1,2018.Published January 2018.Originallyapproved in 1997.Last previous edition approved in 2017 as C1368 10(2017).DOI:10.1520/C1368-18.2The boldface numbers in parentheses refer to the list of references at the end ofthis standard.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 3.1.4 environment,nthe aggrega